How do I know if I have product-market fit before I try to grow?

The short answer

Run the Sean Ellis survey: if 40% or more of users would be 'very disappointed' without your product, you likely have fit worth scaling. Below that, growth spend just accelerates churn. Retention curves that flatten (not decay to zero) are the other hard signal.

Go deeper, your way

2 hand-picked resources. Pick how you want to dig in.

📄 Article

Free Beginner

Why we picked it The original, still-used test for whether you have product-market fit, from the person who coined 'growth hacking' and grew Dropbox and others.

The Sean Ellis Product-Market Fit Survey (40% Test)

From Startup Marketing / GrowthHackers by Sean Ellis ~10 min read

Ask users how they'd feel if they could no longer use your product.
If 40%+ say 'very disappointed', you likely have fit worth scaling.
Below 40%, growth spend accelerates churn instead of revenue.

Open startup-marketing.com →

📄 Article

Freemium Intermediate

Why we picked it Lenny distills how the best product teams pick a single North Star that captures real customer value and drives the whole growth model, with concrete company examples.

The North Star Playbook & Choosing Your Growth Metrics

From Lenny's Newsletter by Lenny Rachitsky ~20 min read

A good North Star metric measures delivered customer value, not vanity signups.
Break the North Star into a small set of input metrics you can actually move.
Fewer, well-chosen metrics reviewed weekly beat sprawling dashboards nobody reads.

Open lennysnewsletter.com →

Terms in this answer

Product-Market Fit Retention Churn

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